JP2017180915A - Fuel supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel supply system capable of reducing possibility of fermentation and heating of accumulated fuel on a bottom part of a bucket conveyor.SOLUTION: Buckets 12 provided with a predetermined interval to a belt 21 includes a scraping member 50 configured to, when the bucket passes a bottom part of a case 20, scrape out accumulated fuel F accumulated on the bottom part. Accordingly, the scraping member 50 can scrape out part of the accumulated fuel F accumulated on the bottom part of the case 20. Consequently, an accumulation amount of the accumulated fuel F can be reduced, thereby reducing the possibility of fermentation and heating of the accumulated fuel.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a fuel supply system.

  Conventionally, a furnace described in Patent Document 1 is known as a furnace for burning fuel. In this furnace, fuel such as biomass fuel, which is an organic resource derived from animals and plants excluding fossil resources, is burned in a combustion furnace. Such a fuel supply system that supplies fuel to the furnace sometimes includes a bucket conveyor that supplies fuel to the fuel storage unit.

JP 2004-36490 A

  Here, when the fuel is transported using the bucket conveyor, the fuel sometimes accumulates at the bottom of the case. If such deposited fuel increases, the fuel may ferment and generate heat. Accordingly, there has been a demand for a fuel supply system that can reduce the possibility of fermentation and heat generation of such deposited fuel.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a fuel supply system that can reduce the possibility of fermentation and heat generation of accumulated fuel at the bottom of a bucket conveyor.

  In order to solve the above problems, a fuel supply system according to the present invention is a fuel supply system that supplies fuel into a furnace that burns fuel, and includes a bucket conveyor that supplies fuel to a fuel storage unit that stores fuel. The bucket conveyor includes a belt extending in the vertical direction, a plurality of buckets that are provided at a predetermined interval with respect to the belt and that convey the fuel upward by driving the belt, and a case that accommodates the belt and the bucket. The bucket includes a scraping member that scrapes the fuel deposited on the bottom when passing through the bottom of the case.

  In this fuel supply system, the bucket provided at a predetermined interval with respect to the belt includes a scraping member that scrapes the deposited fuel deposited on the bottom portion when passing through the bottom portion of the case. Therefore, the scraping member can scrape the fuel deposited on the bottom of the case. Thus, the possibility of fermentation and heat generation of the deposited fuel can be reduced by reducing the amount of deposited fuel deposited.

  In the fuel supply system according to the present invention, the scraping member may be provided in a bucket of 10% or more of the entire bucket. With such a configuration, the deposited fuel can be scraped out by the scraping member with sufficient frequency. As a result, it is possible to prevent the deposited fuel from being solidified and becoming difficult to be scraped off by the scraping member.

  In the fuel supply system according to the present invention, the scraping member may be formed in a comb shape. Such a configuration makes it easy to scrape the deposited fuel.

  In the fuel supply system according to the present invention, a scraping member having comb teeth according to the first pattern is provided for one bucket among the plurality of buckets, and a second pattern is provided for the other buckets. A scraping member having such comb teeth is provided, and a position at which the comb teeth according to the first pattern pass through the bottom deposited fuel is different from a position at which the comb teeth according to the second pattern pass. It's okay. With such a configuration, it is possible to improve the uniformity of scraping of the deposited fuel regardless of the position.

  In the fuel supply system according to the present invention, the scraping member may include a non-ferrous material. With such a configuration, even when the deposited fuel contains a metal or the like, it is possible to suppress the occurrence of a spark or the like at the time of contact between the metal and the scraping member.

  According to the present invention, the possibility of fermentation and heat generation of the deposited fuel at the bottom of the bucket conveyor can be reduced.

FIG. 1 is a schematic configuration diagram showing a fuel supply system according to the present embodiment. Drawing 2 is a schematic structure figure which looked at the bucket conveyor of the fuel supply system concerning this embodiment from the side. FIG. 3 is an enlarged view showing the vicinity of the bottom of the bucket conveyor. FIG. 4 is an enlarged cross-sectional view of the bucket. FIG. 5 is a view for explaining the structure of the comb teeth of the scraping member.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the same or corresponding elements are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a schematic configuration diagram showing a fuel supply system according to the present embodiment. As shown in FIG. 1, the fuel supply system 1 is a system that supplies fuel into a furnace 60 that burns fuel. The kind of the furnace 60 is not specifically limited. Further, the type of fuel to be supplied is not particularly limited. The fuel supply system 1 includes a hopper 2, a conveyor 3, a bucket conveyor 4, a conveyor 6, a bunker (fuel storage unit) 7, and a conveyor 8.

  The hopper 2 is a device that stores fuel supplied from the outside and drops and supplies the fuel to the lower conveyor 3. The transport conveyor 3 is a device that transports fuel in the horizontal direction by the belt conveyor 10. One end side of the belt conveyor 10 is disposed below the hopper 2. The fuel dropped from the hopper 2 is supplied to one end side of the belt conveyor 10 and is conveyed to the other end side by the belt conveyor 10. A bucket conveyor 4 is provided on the other end side of the belt conveyor 10.

  The bucket conveyor 4 is an apparatus that is connected to the transport conveyor 3 on the lower end side and transports the fuel supplied from the transport conveyor 3 upward on the lower end side. The bucket conveyor 4 includes a belt conveyor 11 extending in the vertical direction and a bucket 12 connected to the belt conveyor 11. The buckets 12 are provided at a predetermined pitch on the belt of the belt conveyor 11. The bucket 12 receives the fuel transported from the belt conveyor 10 of the transport conveyor 3 on the lower end side of the bucket conveyor 4. The bucket 12 that has received the fuel is conveyed upward by the belt conveyor 11. The bucket 12 reverses on the upper end side of the bucket conveyor 4 and discharges the held fuel from a discharge unit 13 provided on the upper end side of the bucket conveyor 4.

  The conveyor 6 conveys the fuel discharged from the discharge unit 13 of the bucket conveyor 4 in the horizontal direction. The conveyor 6 conveys the fuel supplied from the bucket conveyor 4 on one end side to the other end side by a belt conveyor or a screw conveyor. The transport conveyor 6 drops the transported fuel into the bunker 7 on the other end side. The bunker 7 is a device that stores the fuel transported from the transport conveyor 6. A reclaimer 16 is provided at the bottom of the bunker 7. The reclaimer 16 is a member that extends in the radial direction from the discharge port 17 provided at the center position of the bottom of the bunker 7 to the outer peripheral side. The reclaimer 16 swirls around the discharge port 17 to collect fuel from the entire bottom surface of the bunker 7 and discharge it from the discharge port 17. The conveyor 8 conveys the fuel dropped from the discharge port 17 of the bunker 7 in the horizontal direction. The conveyor 8 conveys the fuel supplied from the bunker 7 on one end side to the other end side by a belt conveyor or a screw conveyor. The transfer conveyor 8 drops the transferred fuel into the furnace 60 on the other end side.

  Next, the detailed configuration of the bucket conveyor 4 will be described with reference to FIGS. FIG. 2 is a schematic configuration diagram of the bucket conveyor 4 as viewed from the side. FIG. 3 is an enlarged view showing the vicinity of the bottom of the bucket conveyor 4. FIG. 4 is an enlarged cross-sectional view of the bucket. 4 shows a cross-sectional view of the bucket when viewed from the opposite side in the width direction to FIG. FIG. 5 is a view for explaining the structure of the comb teeth of the scraping member. As shown in FIG. 2, the bucket conveyor 4 includes a belt conveyor 11, a bucket 12, and a case 20. In the present embodiment, since the fuel is transported from below to above, the upward direction may be referred to as “conveyance direction D1”.

  The belt conveyor 11 includes a belt 21 that extends in the vertical direction, and rotating shaft members 22 and 23 that guide the belt 21. The rotating shaft member 22 is disposed on the bottom side of the bucket conveyor 4, and the rotating shaft member 22 is disposed on the upper side of the bucket conveyor 4. The rotary shaft members 22 and 23 are cylindrical members extending in the horizontal direction. A driving device (not shown) is connected to at least one of the rotating shaft members 22 and 23, and is driven to rotate about the rotating axis. In the figure shown in FIG. 2, the rotating shaft members 22 and 23 rotate clockwise. In addition, the height in the up-down direction of the bucket conveyor 4 is about 20-60 m. The speed of the belt conveyor 11 is about 1.6 to 2.2 m / s.

  The belt 21 is an endless belt-like member that is stretched between the rotary shaft member 22 and the rotary shaft member 23. Of the belt 21, the conveying portion 24 extending in the vertical direction between one end portion in the horizontal direction of the rotating shaft member 22 and the rotating shaft member 23 (the left end portion in FIG. 2) includes the rotating shaft member 22, 23 is moved in the transport direction D1 (that is, upward). The return portion 26 extending in the vertical direction between the other end portions in the horizontal direction of the rotating shaft member 22 and the rotating shaft member 23 (the end portion on the right side in FIG. 2) of the belt 21 includes the rotating shaft member 22, By the rotational drive of 23, it moves to the conveyance direction D1 opposite side (namely, downward). Note that the belt 21 forms a lower curved portion 27 that curves in a semicircular shape along the rotary shaft member 22 at the lower half position of the lower rotary shaft member 22. In the upper half position of the upper rotary shaft member 23, the belt 21 forms an upper curved portion 28 that curves in a semicircular shape along the rotary shaft member 22.

  A plurality of buckets 12 are members that are provided at a predetermined interval with respect to the belt 21 and convey the fuel upward by driving the belt 21. Here, the bucket 12 is attached to the outer peripheral surface of the belt 21 at a constant interval with respect to the direction in which the belt 21 extends. The interval between the buckets 12 is arbitrarily set in relation to the rotational speed (that is, the bucket feed speed). In a state where the bucket 12 is positioned at the conveyance portion 24 of the belt 21, the bucket 12 moves upward in the conveyance direction D1. In a state where the bucket 12 is positioned on the upper curved portion 28, the bucket 12 turns clockwise along the upper semicircular portion of the rotating shaft member 23. In a state where the bucket 12 is positioned at the return portion 26 of the belt 21, the bucket 12 moves downward, which is the opposite side of the transport direction D1. In a state where the bucket 12 is positioned at the lower curved portion 27, the bucket 12 turns clockwise along the lower semicircular portion of the rotary shaft member 22.

  The bucket 12 has a shape having an opening that opens toward the upper side in a state where the bucket 12 is located on the transport portion 24 of the belt 21 and is moving upward in the transport direction D1. The configuration of the bucket 12 will be described with reference to FIG. 3 and FIG. 4, but the following description is based on the posture when the bucket 12 is positioned on the conveyance portion 24 of the belt 21. As shown in FIGS. 3 and 4, the bucket 12 is fixed to the outer peripheral surface of the belt 21, and includes a mounting wall portion 31 extending in the vertical direction and a bottom wall portion 32 extending from the lower end of the mounting wall portion 31 to the outer peripheral side. The bottom wall portion 32 includes an inclined wall portion 33 extending obliquely upward from the outer peripheral end portion, and side wall portions 34 formed on both end sides in the width direction. An area surrounded by the upper end portions of the attachment wall portion 31, the inclined wall portion 33, and the side wall portion 34 is not blocked by the wall portion, and an opening 36 is formed. Note that, in the bucket 12, the upper end portion 33 a of the inclined wall portion 33 is a portion located on the outermost peripheral side (that is, a portion closest to the inner surface of the case 20). A scraping member 50 is provided on the upper end portion 33a, and a detailed configuration of the scraping member 50 will be described later.

  As shown in FIGS. 2 and 3, the case 20 is a member that accommodates the belt conveyor 11 including the belt 21 and the bucket 12. The case 20 has a tubular structure extending in the vertical direction so as to surround the belt conveyor 11 extending in the vertical direction and the bucket 12 provided in the belt conveyor 11. Specifically, the case 20 mainly includes side wall portions 41 and 42, an upper wall portion 43, and a bottom wall portion 44. The side wall portion 41 extends in the up-down direction at a position separated from the conveying portion 24 of the belt 21 toward the outer peripheral side. The side wall portion 42 extends in the up-down direction at a position spaced from the outer peripheral side with respect to the conveyance portion 24 of the belt 21. The upper wall portion 43 is provided at a position spaced from the upper curved portion 28 toward the outer peripheral side at the upper end portions of the side wall portions 41 and 42. The bottom wall portion 44 is provided at a position spaced from the lower curved portion 27 toward the outer peripheral side at the lower end portions of the side wall portions 41 and 42. Similarly to the lower curved portion 27, the bottom wall portion 44 has a semicircular cross-sectional shape that curves downward. Moreover, the side wall part is provided in the both ends in the width direction of each wall part. An inlet 46 for receiving fuel supplied from the conveyor 3 is formed between the side wall 41 and the bottom wall 44 on the conveyance side. A discharge portion 13 for discharging the fuel conveyed by the bucket is formed between the return side wall portion 42 and the upper wall portion 43. The discharge part 13 extends obliquely downward from the upper wall part 43. As the bucket 12 turns at the upper curved portion 28 and the opening 36 is directed downward from above, the fuel in the bucket 12 falls and is discharged from the discharge portion 13 to the outside of the case 20. A receiving portion 70 that receives fuel falling from the bucket 12 may be formed between the discharge portion 13 and the side wall portion 42. The said receiving part 70 may be comprised including a nonferrous material.

  Here, deposited fuel F is formed on the bottom wall portion 44 by depositing fuel. In order to reduce the thickness of the deposited fuel F, the bucket 12 includes a scraping member 50 that scrapes the deposited fuel F deposited on the bottom portion when passing through the bottom portion of the case 20. The scraping member 50 is provided on the upper end portion 33 a of the inclined wall portion 33 of the bucket 12.

  Specifically, as shown in FIGS. 4 and 5, the scraping member 50 is formed in a comb shape having a plurality of comb teeth 51. The scraping member 50 includes a flat plate portion 52 for joining to the inclined wall portion 33 and a plurality of comb teeth 51 formed at a constant pitch in the width direction at the upper end of the flat plate portion 52. The scraping member 50 may be configured to include a non-ferrous material. As the non-ferrous material, flame retardant rubber, aluminum, resin or the like may be adopted. The entire scraping member 50 may be a non-ferrous material, or only a part (for example, only the comb teeth 51) may be a non-ferrous material.

  The flat plate portion 52 has a rectangular plate shape having substantially the same total length as the total length in the width direction of the inclined wall portion 33 of the bucket 12 (see FIG. 5). In a fixed region near the upper end portion 33a of the inclined wall portion 33, a fixed portion 39 for attaching the scraping member 50 is formed over the entire width direction. Accordingly, the flat plate portion 52 is overlapped with the fixed portion 39 of the bucket 12 and joined using the bolts 61. Specifically, the flat plate portion 52 is sandwiched between the fixed portion 39 and the rectangular fixing bracket 62, and the bolt 61 is inserted into the holes formed in the fixing bracket 62, the flat plate portion 52 and the fixed portion 39 from the outside of the fixing bracket 62. Insert and tighten. In the form shown in FIG. 4, the scraping member 50 is attached to the outer surface side of the inclined wall portion 33. As a result, the fuel scraped by the scraping member 50 can smoothly enter the bucket 12 without being obstructed by the bolts 61 and the fixtures 62. However, the scraping member 50 may be attached to the inner surface side of the inclined wall portion 33.

  The plurality of comb teeth 51 are formed at a constant pitch in the width direction at the upper end portion of the flat plate portion 52. A groove 53 is formed between adjacent comb teeth 51. The comb teeth 51 protrude upward from the upper end portion 33 a of the bucket 12. As shown in FIG. 4, the comb teeth 51 protrude from the upper end portion 33 a at the same angle as the inclination angle of the inclined wall portion 33, but an angle different from that of the inclined wall portion 33 due to the bending of the comb teeth 51. May protrude from the upper end 33a. In the example shown in FIG. 5, the comb teeth 51 have a trapezoidal shape, but the shape is not particularly limited, and may have a triangular shape or a curved shape. The groove 53 also has a trapezoidal shape, but the shape is not particularly limited, and may have a triangular shape or a curved shape. The amount of protrusion of the comb teeth 51 is not particularly limited, but the protrusion is such that the tip of the comb teeth 51 is separated from the inner surface 44 a of the bottom wall portion 44 by a predetermined distance when the bucket 12 is turning the bottom wall portion 44. The amount is preferably set. As a result, the comb teeth 51 can be prevented from being caught by the inner surface 44a or the solidified deposited fuel F.

  Here, at least two types of scraping members 50 may be provided for the belt conveyor 11. That is, among the plurality of buckets 12 provided on the belt 21, one bucket 12 is provided with a scraping member 50 </ b> A (upper stage in FIG. 5) having comb teeth 51 </ b> A according to the first pattern. In contrast, a scraping member 50B (lower stage in FIG. 5) having comb teeth 51B according to the second pattern may be provided. In the example shown in FIG. 5, the comb teeth 51A of the scraping member 50A and the comb teeth 51B of the scraping member 50B have different phases, and the groove portion 53B is disposed at a position corresponding to the comb tooth 51A, and corresponds to the groove portion 53A. The comb teeth 51B are arranged at the positions. Thereby, the position through which the comb teeth 51A according to the first pattern pass with respect to the deposited fuel F at the bottom and the position through which the comb teeth 51B according to the second pattern pass are different from each other.

  In the example shown in FIG. 5, the comb teeth 51 </ b> A according to the first pattern and the comb teeth 51 </ b> B according to the second pattern are different only in phase, and the shape and size of each comb tooth 51 are different. The pitch is the same. However, the comb teeth 51A according to the first pattern and the comb teeth 51B according to the second pattern may have different shapes and pitches of the comb teeth 51 in place of or in addition to the phase. For example, the comb teeth 51A according to the first pattern have a large width in the width direction of the comb teeth 51A, and the pitch is rough, and the comb teeth 51B according to the second pattern have a width of the comb teeth 51B per one. The direction dimension may be small and the pitch may be dense. Further, in one scraping member, the comb teeth 51 are formed in a constant pattern (for example, the pitch and the shape of the comb teeth are constant over the entire width direction), but the pattern may change in the width direction. For example, the pitch and the size of one comb tooth may be different depending on the position in the width direction. Further, the comb teeth 51 may be provided with different pattern changes between the first pattern and the second pattern. Moreover, although the belt conveyor 11 is provided with the scraping member 50 of two types of patterns, you may be provided with the scraping member 50 of three or more types of patterns.

  Here, the belt conveyor 11 includes a plurality of buckets 12, but the scraping members 50 may not be provided in all the buckets 12, and may be provided in some of the buckets 12. In this case, the scraping member 50 is preferably provided in the bucket 12 at a ratio of 10% or more in the entire bucket 12. That is, it is only necessary that the scraping members 50 are provided at a ratio of 10 or more for 100 buckets 12. In relation to the speed of the belt conveyor 11, the bucket 12 having the scraping member 50 may pass through the deposited fuel F at a rate of once every 3 to 5 seconds. In addition, although it is preferable that the scraping member 50 is provided with respect to the plurality of buckets 12 at regular intervals, the scraping members 50 may not be regular intervals. However, the quantity of the scraping member 50 with respect to the whole bucket 12 is not specifically limited, The scraping member 50 should just be provided in the one bucket 12 with respect to the whole belt conveyor 11 at least.

  Next, the operation and effect of the fuel supply system 1 according to this embodiment will be described.

  In the fuel supply system 1, the bucket 12 provided at a predetermined interval with respect to the belt 21 includes a scraping member 50 that scrapes the accumulated fuel F accumulated on the bottom portion when passing through the bottom portion of the case 20. Therefore, the scraping member 50 can scrape the deposited fuel F accumulated on the bottom of the case 20. Thus, by reducing the amount of deposition of the deposited fuel F, the possibility of fermentation and heat generation of the deposited fuel can be reduced.

  Specifically, as shown in FIG. 3, when the bucket 12 passes through the lower curved portion 27 of the belt 21, it turns clockwise along the lower semicircular portion of the rotary shaft member 22. At this time, the upper end portion 33a corresponding to the outermost peripheral portion of the bucket 12 turns so as to draw an arc along the curved shape of the inner surface 44a at a position spaced from the inner surface 44a of the bottom wall portion 44. Therefore, by providing the scraping member 50 at the upper end portion 33a of the inclined wall portion 33 of the bucket 12, the scraping member 50 is swung in a circular arc along the curved shape of the inner surface 44a, so that the surface of the inner surface 44a is turned. The accumulated fuel F that has accumulated can be scraped out and recovered by the bucket 12. At this time, since the tip of the scraping member 50 is separated from the inner surface 44a, it is not possible to scrape all of the deposited fuel F, and a part (portion indicated by F1) remains. However, since the amount of deposition can be reduced by scraping out a portion of the surface layer portion (the portion indicated by F2), the possibility of fermentation and heat generation of the deposited fuel F can be reduced.

  In the fuel supply system 1, the scraping member 50 may be provided in the bucket 12 at a ratio of 10% or more with respect to the entire bucket 12. With such a configuration, the deposited fuel F can be scraped out by the scraping member 50 with sufficient frequency. Thereby, it is possible to suppress the scraped member 50 from being easily scraped by the deposited fuel F being solidified.

  In the fuel supply system 1, the scraping member 50 is formed in a comb shape. Such a configuration facilitates scraping the deposited fuel F.

  In the fuel supply system 1, a scraping member 50 </ b> A having comb teeth 51 </ b> A according to the first pattern is provided for one bucket 12 among the plurality of buckets 12, and a second is provided for the other buckets 12. A scraping member 50B having comb teeth 51B according to the pattern is provided. The position at which the comb teeth 51A according to the first pattern pass with respect to the deposited fuel F at the bottom is different from the position at which the comb teeth 51B according to the second pattern pass. With such a configuration, the uniformity of scraping of the deposited fuel F can be improved regardless of the position.

  In the fuel supply system 1, the scraping member 50 may be configured to include a non-ferrous material. With such a configuration, even when a metal or the like is contained in the deposited fuel F, it is possible to suppress the occurrence of a spark or the like when the metal and the scraping member 50 come into contact with each other.

  The present invention is not limited to the embodiment described above.

  For example, in the above-described embodiment, the scraping member has a comb-like shape, but the shape of the scraping member is not particularly limited. For example, a scraping member in which flat teeth protrude from the upper end of the inclined wall portion of the bucket may be employed. Alternatively, a scraping member having an L-shaped plate shape that bends toward the outside of the bucket when viewed from the width direction (the tip of the scraping member has a linear shape, not a comb tooth) May be adopted. Alternatively, a scraping member having a corrugated shape may be employed instead of the comb-teeth shape.

  DESCRIPTION OF SYMBOLS 1 ... Fuel supply system, 4 ... Bucket conveyor, 7 ... Bunker (fuel storage part), 12 ... Bucket, 20 ... Case, 21 ... Belt, 50 ... Scraping member, 51 ... Comb tooth, 60 ... Furnace.

Claims (5)

A fuel supply system for supplying the fuel into a furnace for burning fuel,
A bucket conveyor for supplying the fuel to a fuel storage section for storing the fuel;
The bucket conveyor is
A belt extending in the vertical direction;
A plurality of buckets provided at predetermined intervals with respect to the belt, and conveying the fuel upward by driving the belt;
A case for accommodating the belt and the bucket,
The fuel supply system, wherein the bucket includes a scraping member that scrapes the fuel deposited on the bottom when passing through the bottom of the case.   2. The fuel supply system according to claim 1, wherein the scraping member is provided in the bucket at a ratio of 10% or more of the entire bucket.   The fuel supply system according to claim 1, wherein the scraping member is formed in a comb-teeth shape. Of the plurality of buckets,
A scraping member having comb teeth according to the first pattern is provided for one bucket,
For other buckets, a scraping member having comb teeth according to the second pattern is provided,
The position at which the comb teeth according to the first pattern pass with respect to the deposited fuel at the bottom is different from the position at which the comb teeth according to the second pattern pass. Fuel supply system.   The fuel supply system according to any one of claims 1 to 4, wherein the scraping member includes a non-ferrous material.

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